Changes in PAH and 3-MCPDE contents at the various stages of Camellia oleifera seed oil refining

Objectives Polycyclic aromatic hydrocarbons (PAHs) and 3-monochloropropane-1,2-diol ester (3-MCPDE) were studied in camellia oil. It is important to study the changes in the content of PAHs and 3-MCPDE at different refining stages (from crude oil to the final refined oil product) to elucidate the influence of the refining procedures on their change.Materials and methods The PAHs and 3-MCPDE in camellia oil from different refining stages (from crude oil to the product) of a plant were analyzed by gas chromatography-mass spectrometry and calculated by the internal standard method.Results The overall PAH content was (79.64 +/- 2.43) mu g/kg in crude camellia oil. After refining treatment, the PAH content decreased to (18.75 +/- 0.55) mu g/kg. The 3-MCPDE content increased during the refining process from 0 mg/kg in the crude oil to 4.62 mg/kg in the refined oil product.Conclusions This is the first study to simultaneously monitor changes in both PAH and 3-MCPDE contents during the production of camellia oil. These results confirmed the effectiveness of the refining method on PAH removal and the increase in 3-MCPDE at high temperature. It is suggested that novel processing methods or refining parameters need further optimization to decrease the overall concentrations of PAHs and 3-MCPDE in camellia oil.